6,7 Substituted 3-hydroxymethyl- 1 phenyl, benzyl or phenylethyl substituted isoquinolines

ABSTRACT

The present invention provides new 3-hydroxy-methylisoquinolines having useful therapeutic, especially spasmolytic and cardiovascular, properties corresponding to the general formula:   IN WHICH R represents a hydrogen atom or an acyl group; n is 0, 1 and 2; R1 and R2, which may be identical or different, each represents a hydrogen atom, a benzyl group or a C1-C3 alkyl group, or R1 and R2, together with the oxygen atoms in positions 6 and 7 to which they are bonded, form an alkylenedioxy chain, in particular a methylenedioxy chain; and Ar represents an aromatic group; and their acid addition salts.

United States Patent Valette 6,7 SUBSTITUTED S-HYDROXYMETHYL- l PHENYL, BENZYL OR PHENYLETHYL SUBSTITUTED ISOQUINOLINES [75] Inventor: Raymond Valette, Saulx Les Chartreux, France (73] Assignee: Albert & Rowland S.A., Paris,

France [22 Filed: Sept.21, 1972 21 Appl. No.: 290,813

[30] Foreign Application Priority Data Sept. 22, 1'971 United Kingdom i. 44240/7] [52] US. Cl 260/289 C; 260/268 C; 260/283 S;

260/287 R; 260/330.5; 424/258 [51] Int. Cl C07d 33/38 [58] Field of Search 260/289 R. 289 A [56] References Cited UNITED STATES PATENTS 7/l954 Shepard 260/289 R 8/l967 Biel i 260/287 R l/l974 Yamato 260/287 R OTHER PUBLICATIONS Mueller et al., Chemical Abstracts, 64223r, p. 6040, 1967.

[ 5] June 24, 1975 Primary Examiner-Donald G. Daus Assistant Examiner-David E. Wheeler Attorney, Agent, or Firm-Stevens, Davis, Miller & Mosher [57] ABSTRACT The present invention provides new 3-hydroxymethyl isoquinolines having useful therapeutic, especially spasmolytic and cardiovascular, properties corresponding to the general formula:

5 Claims, No Drawings 6,7 SUBSTITUTED 3-HYDROXYMETHYL-1 PHENYL, BENZYL OR PHENYLETHYL SUBSTITUTED ISOQUINOLINES The present invention relates to papaverine derivatives, more particularly to 3-hydroxymethylisoquinolines which are substituted in positions I 6 and 7.

It is known that papaverine (6,7-dimethoxy-l-(3A- dimethoxy-benzyl)-isoquinoline) and perparine (6,7- diethoxy-l-(3,4-diethoxy-benzyl)isoquinoline) have a therapeutic activity of short duration. The purpose of this invention is to produce analogues of papaverine and perparine which have a longer lasting action and which possess better spasmolytic and cardiovascular properties.

It has, surprisingly, been found that it is possible, firstly, to introduce a CH OH group into the 3-position of isoquinoline without destroying the substituents present in positions 6 and 7 and without hydrogenating positions l, 2, 3 and 4 and, secondly, to obtain either water-soluble analogues or esters, especially esters with a long fatty chain, by esterification of the 3CH OH group with suitable acid chlorides.

The present invention provides:

a. the isoquinolines of the general formula:

,R O I CH -OR (CIH in which R represents a hydrogen atom or an acyl group; n is 0, l or 2; R and R which may be identical or different, each represents a hydrogen atom, a benzyl group or a C,C alkyl group, or R and R together with the oxygen atoms in positions 6 and 7 to which they are bonded form an alkylenedioxy chain, in particular a methylenedioxy chain, and Ar represents an aromatic group; and

b. their acid addition salts.

By aromatic group" as used herein is meant not only optionally substituted aryl and aralkyl groups, but also their optionally substituted hetero-aromatic isosteres.

According to one embodiment of this invention, Ar represents an a-naphthyl, B-naphthyl, Z-furyl, 2- thienyl, 2-(5-nitrofuryl), 2 (S-nitrothienyl),

which may be identical to, or different from, that of the chain OR R O, A in that case being a hydrogen atom.

According to this invention, the acyl groups which R may represent include aliphatic, cycloaliphatic and aromatic acyl groups, the aromatic group being, as stated above, true aromatic or hetero-aromatic groups, the preferred acyl groups being the following:

i. groups of the cycloalkyl-alkyl-CO" type, such as 3-cyclopentylpropionyl and 3-cyclohexylpropionyl;

ii. groups of the linear, saturated or unsaturated alkyl-CO" type, containing at least 2 carbon atoms, and preferably at least 7 carbon atoms, such as lauroyl, my ristoyl, palmitoyl, stearoyl, 9-undecylenoyl and heptanoyl; and

iii. acyl groups containing at least one free COOH group, such as hemimalonyl, hemisuccinyl, hemiglutaryl, hemiadipoyl, hemipimeloyl, hemisuberoyl and hemifumaroyl.

The isoquinolines of this invention may be prepared by:

a. dehydrogenating a substituted 3,4-dihydroisoquinoline of the general formula:

I COOCH wherein R,, R Ar and n are as defined above;

b. treating the isoquinoline 3-methylcarboxylate of the formula:

\ -cooca ,n R20 (III) thus obtained with a hydride reducing agent in order to yield the compound of formula (I) in which R H; and

c. optionally, esterifying the 3-methanolic derivative thus formed to yield a compound of formula (I) in which R acyl.

According to one embodiment of this process, dehydrogenation of the starting products 11 is ca ried out by means of sulphur. Dehydrogenation is preferably carried out at about C. in the presence of more than 1 mol of sulphur per 1 mol of 3,4-dihydro-is0quinoline ll.

Suitably the hydride reducing agent is chosen from amongst the group consisting of LiAlH NaBH KBH, and LiBH... Preferably, an amount greater than or equal to 1 mol of LiAlH NaBH KBH, or LiBH, is used per 1 mol of ester of formula (Ill).

Dehydrogenation by means of sulphur, followed by reduction by means of a hydride such as LiAlH,, NaBH KBH, and LiBH has the advantage of not destroying the OR, and CR groups in positions 6 and 7 of the starting products of formula (11). In effect, the only method known hitherto for the preparation of a 3-hydroxymethyl derivative of l-aryl-isoquinoline involves the direct treatment of a 3-phenoxymethyl-3,4- dihydro-l-aryl-isoquinoline with a 48% strength aqueous solution of HBr for 8 hours under reflux, (see A. BOSE et al., J. Ind. Chem. Soc, 38, No. 4,216 (1961)). Since such a treatment destroys all the OR, and R substituents, this method cannot be applied to the preparation of the products of formula (I).

The compounds of formula (1) can, in addition, be converted into addition salts with acids. by bringing them into contact with an inorganic or organic acid, such as hydrochloric, hydrobromic, hydriodic, mcthanesulphonic, para-toluenesulphonic or perchloric acid.

In order to prepare the derivatives in which R aryl, it is possible to react a compound of formula (I) in which R H with an acid anhydride of formula ROR or an acid chloride of formula RCl wherein R represents an acyl group as defined above.

The starting materials of formula (11) can be obtained by several methods. It is possible, in particular. to use the method described by A. GALAT (J. Am. Chem. 800., 72, 4436 (1950) and 73, 3654 (1951)) to obtain the products of the formula:

COOCH I R 0 IIa) wherein R, and R are defined as stated above. it is also possible to use the method described in Cibas German Pat. No. 399,805 to obtain the other starting products by cyclising substituted acyl-amino-acetic acids. It is also possible to employ the method of SASAKI, (Ber. 54, pages 163 and 2056 (1921)) starting with diacetopiperazine to prepare the aminoacids and then their amides by acylation before cyclising.

The present invention also relates to the use of the compounds of this invention for therapeutic purposes. The therapeutic compositions of this invention contain, as active ingredient, at least one compound of formula (1), or one of its acid addition salts, combined with a physiologically acceptable vehicle or excipient.

The following Examples further illustrate the present invention:

EXAMPLE 1 6,7-Dimethoxy-3-hydroxymethyll 3 ,4-dimethoxybenzyl )-isoquinoline a. 5 g 12.5 millimols) of 3,4-dihydro-6,7-dimethoxy- 3-m ethoxycarbonyll 3 ,4-dimethoxybenzyl isoquinoline and 0.6 g (18.7 millimols) of sulphur, finely ground and intimately mixed, are introduced into a 250 ml Erlenmeyer flask.

The reactor is immersed in an oil bath heated to 150C. After melting, the evolution of H 5 starts rapidly. lt is complete after a few minutes. After cooling, the mass is taken up in 100 ml of cold 5% strength HCI. The mixture is filtered to remove the sulphur, and then the product is precipitated by means of NH OH, filtered off, rinsed with water and dried in an oven, for example at 50C. 4.33 g of product, which melts at 179C are obtained. On recrystallisation of this crude product from a methanol/acetone (2:1) mixture, 3.88 g of 6,7- dimethoxy-3-methoxycarbonyll 3 ,4dimethoxybenzyl)-isoquinoline, which melts at ll89C, are obtained. (78% yield).

b. 54 g (1 mol) of potassium borohydride are introduced into l litre of anhydrous methanol, whilst stirring, and 43 g (1 mol) of lithium chloride are added gradually. The temperature of the mixture rises to about 4550C. 15.3 g (0.038 mol) of the ester obtained under a) are introduced, all at once, whilst stirring, into this hot mixture and stirring is then continued for 4 hours. The temperature slowly returns to ambient temperature. The mixture is then filtered and the inorganic residue is washed with methanol and then taken up in chloroform. Evaporation of the methanol under reduced pressure gives a first crop of crystals. The evaporated chloroform liquors give a second crop. The two crops are recrystallised from a cyclohexane/benzene (1:1) mixture and 10 g of 6,7-dimethoxy-3- hydroxymethyl- 1 3,4-dimethoxybenzyl )-isoquinoline, which melts at l56l 58C, are obtained. (70% yield).

Two addition salts with acids, namely the hydrochloride which has a melting poiont of 253C (with decomposition) and the methanesulphonate, were also prepared.

The following example has been given to illustrate the reduction by means of LiAlH EXAMPLE 2 6,7-Dirnethoxy-3-hydroxymethyl-1-(3,4-dirnethoxybenzyl l-isoquinoline 60 g (approximately 0.15 mol) of 6,7-dimethoxy-l- (3,4-dimethoxybenzyl )-3-methoxycarbonylisoquinoline, prepared according to Example 1a, in 750 ml of anhydrous tetrahydrofurane, are placed in a 2 litre Erlenmeyer flask equipped with a stirrer and a nitrogen inlet. The mixture is cooled by means of a bath of water and ice, and stirred and then LiAlH, is added in small amounts of to 200 mg per portion.

The reduction is complete when the red colour which appears after each addition becomes persistent, and this requires a total of about 1 mol of LiAlH, per 1 mol of ester. By isolating and purifying the final product as stated in Example 1, the desired substance, which melts at 156-l58C, is obtained with a yield of 72%.

EXAMPLE 3 Hemisuccinate ester of 6,7-dimethoxy-3- hydroxymethyl-l 3 ,4-dimethoxybenzyl )-isoquinoline.

(Ill

; L\ l --(3Cll OCH The cardiovascular with water and dried in an oven at 50C. 10.65 g (95% yield) of a white crystalline product which melts at 176C and is very soluble in water, are obtained. Analysis confirms that this product is the hemisuccinate ester of 6,7-dimethoxy-3-hydroxymethyl-1-(3,4-dimethoxybenzyl)-isoquinoline.

On replacing the succinic anhydride by the acid chloride of 3-cyclohexyl-propionic acid, and following a process analogous to that of Example 3 above, the 3-cyclohexyl-propionate ester of 6,7-dimethoxy-3- hydroxymethyll 3 ,4-dimethoxybenzyl )-isoquinoline is obtained.

Likewise, on replacing the succinic anhydride by acetic anhydride and following the procedure given in Example 3, the corresponding acetate ester, which melts at 134C, is obtained.

By applying one or other of the methods of Examples 1 and 2, and by carrying out an esterification where necessary according to Example 3, a certain number of compounds which have been listed in Tables I and ll below, have been prepared. Table 1 relates to derivalives in which the symbol Ar represents a true aromatic group and includes the products described above in Ex amples l to 3. Table ll relates to derivatives in which the symbol Ar is a hetero-aromatic group. In these tables, the melting points have been stated in every case wherein they were taken.

The products according to the invention have spasmolytic properties which are better than those of papaverine. They possess a cardiovascular effect which is analogous to that of papaverine, but this effect is longer-lasting than that of papaverine.

The spasmolytic properties have been demonstrated in vitro and in vivo. In vitro, the experiments were carried out, firstly, on the isolated rat duodenum with regard to barium chloride used as the agent causing contracture, and secondly, on the isolated guinea pig ileum with regard to bradykinin used as the agent causing contracture. The results listed in Table 111 show that the products of the invention are as active as papaverine in vitro.

effect, and especially the vasodilatory activity, has been investigated in anaesthetised dogs. The results relating to the pulse rate and to the average coronary flow rate have been summarised in Table V] below, relative to control animals, that is to say that a percentage increase or decrease has been stated. The results have been compared with known products, namely papaverine hydrochloride and reference coronary vasodilators such as Persantin or 2,6-bis- (diethanolamino)-4,S-dipiperidino-pyrimido-[5,4-dlpyrimidine and lntensain or 3-(Bdiethylaminoethyl)-4- methyl-7-(carbethoxymethoxy )-2H- l-benzopyran- 2-one hydrochloride.

Table VI makes it possible to verify that the compounds of the formula I and their non-toxic addition salts with acids have an activity of the same order of magnitude as that of papaverine but of longer duration.

The values relating to the comparative toxicities have been listed in Table Vll below. Although papaverine is in the form of the hydrochloride, which is a substance with a low toxicity, it is obvious from Table Vll that the products of the invention are even less toxic than papaverine hydrochloride.

In conclusion, the compounds according to the invention, like papaverine, are thus useful as vasodilators TABLE I cn ox A2 2 (cs A1 l 1 I l i ,v s 1,- Pro- Farm 3. R A A, A n R l luillill'lf do i i duct; 1 2 5 point r l N 3 l 1 1 l P 1'6 3 l i .L tree base V11 CB 00h OCH r .l.,- l 2 hydrochloride CH CH OCH 00111 1-1 1 H 1 255(2.) 5 2 l l 5 methanesulphona'te CH3 CH OCH OCH H l. y H 7. /.I 1 5 l i 4 free base CH CH (CH OCH-5 31'. l :CCCE -CI-I GOCH 33 10 a; l 5 free base CH CH OCH 02:1 a 1 l (DC-CH 15 law 5:1' l e hydrocnloride 03 01-1 oca cos, a 1 00-03 259 i J l a I 1 l 7 taee have 0 l'1 (3 .1 .Ov;.a5 (I 4 11 l .t 1m.

i-py y 2--thieny3.

.5-nicrofuryl) 5 CH Z-thienyl free base C r l 2 w. F1 t, 2 i 2 4 I H 1 r u n m 711 1 T r m c .J r i 2 I 0 2 2 H .K 1. 5 2 n v. 1 l 11 C. 7 r 1 A l a .l X 9. e "i w u A. .1 TE t ti 1 I 11$- xiii .E! c av 8 .5 w g Q n 3 1 L C 1 C n C 2 l in H c o I "n. I Q n 1. n "I P H F. u M U, 2 1. F C

R \11!.\.{ 1.11.411. l n l l 1 Y1 ,I. ['114 Y r\ I) \1|\l"1| lli n d .3 4 m A H n h 1.2 n EJ 111 x 1. r .I r c 5 m 5 r) 5 6 0 H H H 1 n a P 2 2 T r 1|. C 2 C C C l 2 A O C O H 9 E I ill; I] .l T 8. m 5 5 w i 7 r 3 L H E u T r B 2 2 2 A A l C n C L O n O .1:

NJ 1 2 H w H K x 2 2 2 2 2 R R C C C l R n l 0 R i t i c n t T o 7 a a n r m 0 C O 9 3 E .1 Q 3 d 6. d d P 0 c i i l 1 c r u r r u r m o e e e o n c s a o r l S 5 S l T O m h C a a a h r h n a. .n 2 F r C R b b b C b C n .3 P r\ .u O a O C O F T .1. C G C I C T 2 I d 3 C A e 3 C .i ll v. e r r r I r r T. e 2 h U f f f n f H. f .n t ii, ii. 11. 1i; l 11;. I o c I u d O O l 3 J w r c) C w O K 8 1 1 1 .3 l A 7. r a 1 TABLE III 10 TABLEIVI Spasmolytic effect in vitro.

Products Rat duodenum Guinea pig ileum (a) (h) (at i Papaverine hydrochloride 2 5 X It] I I I Rd 5002 7.5 X I0"' 033 I0 I Rd 5009 I25 X I0 02 25 X I0 04 Rd 5004 2 5 X It) I 4.5 X I()' 0.2 Rd 5010 5 X I0" 05 4.5 X 0.2 Rd 5022 5 X l0 0.5 3 X It) 0.33 Rd 5023 I0"" 0.25 5 X I0" 02 Rd 5024 6.25 X 10' 0.4 5 X 10 02 Rd 5025 IU 025 1.4 X It) 0.7

Notes:

(at concentration in g/l which decreases by 50% the effect of Bafb on the rut duodenum and of hradykinin on the guinea pig ileum (Iv) relative concentration with respect to pupawrinc h)LII'0CI1ItH'lLIL to which the \aluc I has arbitrarily been assigned The spasmolytic experiments carried out in vivo have shown that all of the products according to the inven tion are much more active than papaverine. The spas molytic properties in vivo have been demonstrated firstly, according to the method of KONZETT modified by HALPERN, Arch. Int. Pliarcodym, (I942), 68, pages 339408, by investigating bronchospasm induced in anaesthetised guinea pigs by bradykinin. acetylcholine and histamine. and secondly, according to the method of LEVY and APFFEL Therapy, 1967, 22, 397. in anaesthetised rabbits by electrical stimulation of the jejunum. The results have been listed respectively in Tables IV and V below.

TABLE IV Spasmolytic effect in vive in anaesthetised guinea pigs.

Doses which decrease by 50% the effect of:

Spasmolytic effect in vivo in rabbits by electrical stimulation of the jejunna.

Products Doses which decrease by 509% the effect of the electrical stimulation. mg/kg Papaverine hydrochloride I0 Rd 5002 I0 Rd 5009 5 Rd 5004 10 Rd 5010 2.5 Rd 5022 2 Rd 5023 2 Rd 5024 I5 Rd 5025 I Cardiovascular effect in anaesthetised dogs.

Products Cardiac frequency Average corenary (al flow rate Papaverine hydrochloride +l9 /l (0.5 mg/kg) +498)? 3 mins.) Persaetin 0 (0.5 mg/kg] I29'/r (42 mins.) (c) Intcnsain 329i (5 mg/kg] 7754 (23 mins.) Rd 5002 +269? (2 mg/kg] '53?! (26 niins.) Rd 5009 +209! (2 mg/kg) /1 (25 mins.) Rd 5004 +I29? (5 mg/kg) 79'/: (I5 rnins.) Rd 50I0 H29 (5 mg/kg) (I2 mins.) Rd 5022 +25% (I mg/kg) I72'/? (16 mins] Rd 5023 +2554 (I mg/kg) I30/1 (l7 mins.) Rd 5024 +2I'li (2 mg/kg) -2209'r (I0 mins.) Rd 5025 +28% (5 mg/kg) |53/P (22 mins.)

Notes:

(a) the A giwn corresponds to the maximum effect for the docs stated in parentheses; (h) unless otherwise stated, the effect given corresponds to an administration of 2 mg/kg of product. the duration of the action is stated in parentheses (the coronary fiuw rate is measured by an electromagnetic flow lnctcr at the anterior coronary artery I: (cl at a dustof 0.5 mpg/kg TABLE Vll Acute toxicity in mice.

Products LD-50 or MLD (a) in rng/kg intravenous subcutaneous oral administration administration administration Papaverine LD-50 37.5 LD-SO 380 LD-SO 2500 hydrochloride Rd 5002 MLD 30 MLD 200 MLD I650 Rd 5009 MLD 200 LD-50 I000 LD-50 3000 Rd 5004 MLD 3000 Rd 50I0 LD 50 I60 MLD 2000 MLD 2000 Rd 5022 LD-50 200 MLD 500 LD-50 2000 Note:

(a) MLD Minimum lethal dust.

I claim: I. A compound of the group consisting of a. isoquinolines of the formula ,9. O I 1 ca on I I (ca 1 J I 2 n l M in which n, is 0, 1 or 2, R is CH C H R has the same meaning as R R and R together with the oxygen atoms to which they are bonded being able to form a methylenedioxy chain, where A is OCH OC H A is OCH OC H A and A considered together being able to form a methylenedioxy chain; A;, is H, OCH and.

b. non-toxic acid addition salts thereof. 2. The isoquinoline of claim I which is 6.7-

dirnethoxy-B-hydroxymethyll 3 .4dimethoxyisoquinoline methane-sulphonate.

5. The isoquinoline of claim 1 which is 6,7-dieth0xy- 3-hydr0xymethyll 3 ,4-dimethoxyphenyl isoquinoline hydrochloride.

UNITED STATES PATENT AND TRADEMARK OFFICE CERTIFICATE OF CORRECTION PATENT NO. I 3, 891, 654

DATED 3 June 24, 1975 |NVENTOR( 1 Raymond Valette It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

[73] Assignee: Albert Rolland S.A.

Signed and Sealed this seventeenth D a Of February 1 976 SE AL I A ttest.

RUTH C. MASON C. MARSHALL DANN ff (ummixsinner uj'Parenrs and Trademarks 

1. A COMPOUND OF THE GROUP CONSISTING OF A. ISOQUINOLINES OF THE FORMULA
 2. The isoquinoline of claim 1 which is 6,7-dimethoxy-3-hydroxymethyl-1-(3,4-dimethoxyphenyl)-isoquinoline hydrochloride.
 3. The isoquinoline of claim 1 which is 6,7-dimethoxy-3-hydroxymethyl-1 -(3,41methane-sulphonate.
 4. The isoquinoline of claim 1 which is 6,7-dimethoxy-3-hydroxymethyl-1-(3,4-dimethoxybenzyl)-isoquinoline methane-sulphonate.
 5. The isoquinoline of claim 1 which is 6,7-diethoxy-3-hydroxymethyl-1-(3,4-dimethoxyphenyl)-isoquinoline hydrochloride. 